In vivo and in vitro NMR spectroscopy reveal a putative novel inborn errorinvolving polyol metabolism

In vivo NMR spectroscopy was performed on the brain of a patient with a leu ko encephalopathy, revealing unknown resonances between 3.5 and 4.0 ppm. In addition, urine and CSF of the patient were measured using high-resolution NMR spectroscopy. Also in these in vitro spectra, unknown resonances were observed in the 3.5-4.0 ppm region. Homonuclear H-1 two-dimensional J-resol ved spectroscopy (JRES) and H-1-H-1 correlation spectroscopy (COSY) were pe rformed on the patient's urine for more accurate assignment of resonances. The NMR spectroscopic studies showed that the unknown resonances could be a ssigned to arabinitol and ribitol. This was confirmed using gas chromatogra phy. The arabinitol was identified as D-arabinitol. The patient is likely t o suffer from an as yet unknown inborn error of metabolism affecting D-arab initol and ribitol metabolism. The primary molecular defect has not been fo und yet. Urine spectra of patients suffering from diabetes mellitus or gala ctosemia were recorded for comparison. Resonances outside the 3.2-4.0 ppm r egion, which are the most easy to recognize in body fluid spectra, allow ea sy recognition of various sugars and polyols. The paper shows that NMR spec troscopy in body fluids may help identifying unknown resonances observed in in vivo NMR spectra. Copyright (C) 2001 John Wiley & Sons, Ltd.